Last Updated Sept 6, 2021
For the past decade, mobile apps have been able to rely on Apple’s Identifier for Advertiser (IDFA) to track users across other companies' apps and websites for targeting and advertising purposes. With Apple's release of iOS 14.5 at the end of April, iOS app developers are now required to request permission to track their users beyond the app in use. With opt-in rates expected to be low, this change is anticipated to impact the entire mobile ecosystem and create challenges for personalized advertising and attribution, impacting the $189 billion mobile advertising industry worldwide.
Flurry Analytics, from Verizon Media, is used in over 1 million mobile applications, providing aggregated insights across 2 billion mobile devices per month. In the below report, we share the weekly opt-in rate as well as the percentage of users with ‘restricted’ app tracking, both in the U.S. and worldwide, following the launch of iOS 14.5.
Flurry determines opt-in rate as ‘Authorized' divided by ('Authorized' + 'Denied'). Restricted app tracking rate is calculated as 'Restricted' divided by ('Authorized' + 'Denied' + 'Restricted '+ ‘Not Determined’).
These app tracking statuses are defined by Apple, and may be summarized as follows:
- ‘Authorized’ represents app users who tapped 'Allow Tracking' via the AppTrackingTransparency (ATT) prompt.
- ‘Denied’ represents two groups of app users, which Apple does not separate:
- Users who saw the prompt and tapped 'Ask App Not to Track’. These users denied tracking for an app via the ATT prompt.
- Users who went to iOS Privacy Settings and toggled 'Allow Apps to Request to Track’ OFF. These users denied tracking for all apps at once, preventing apps from presenting the prompt.
- ‘Restricted’ represents app users with 'Allow Apps to Request to Track' setting OFF and DISABLED. Apple disables this setting for devices with Apple IDs associated with minors, for example. These users never have a choice to select a tracking option and cannot be tracked by default.
- ‘Not Determined’ represents app users who have not seen the prompt and who have toggled 'Allow Apps to Request to Track' setting ON. These users have not been asked yet to select a tracking option and are by default not being tracked.
We calculate the opt-in rate both overall and across apps that have displayed the ATT prompt. We estimate the set of apps that have displayed the ATT prompt by including only apps with more than 1% of active users using iOS 14 versions and above who have authorized tracking. We determine the percentage of users who have authorized tracking as 'Authorized' divided by ('Authorized' + 'Denied' + 'Restricted' + 'Not Determined'). We set a threshold of 1% for the proportion of users who have authorized tracking to exclude internal tests or very limited end-user ATT prompt rollouts.
How do we count app users?
We count the number of Flurry IDs based on the IDFV that are using iOS versions in which the ATT framework is available (iOS 14.0 and above). If a user opts in ('Authorized' tracking) for one app, and opts out ('Denied' tracking) for another app, we consider it as one app user who opts in, and another app user who opts out. In other words, we count app users, not individual users, which means that a single user who selects a tracking option across 2 apps will be counted 2 times.
What do these metrics mean?
Opt-in rate across all apps: Percentage of app users who allow app tracking among app users using iOS 14 versions and above who have chosen to either allow or deny app tracking. Note that denying tracking can be done for a given app via the prompt or for all apps by toggling 'Allow Apps to Request to Track’ OFF in the iOS Privacy Settings. This metric provides an industry-level view into the proportion of app users who have chosen to authorize vs. deny app tracking among all app users who have already selected a tracking option.
Opt-in rate across apps that have displayed the prompt: Percentage of app users who allow app tracking among app users using iOS 14 versions and above who have chosen to either allow or deny app tracking, either directly by going into the iOS Privacy Settings, or when prompted by an app, across apps that have displayed the ATT prompt. This metric is useful for app developers looking to benchmark the opt-in rate of their app as it is calculated specifically across apps that have displayed the prompt.
Restricted app tracking rate: Percentage of app users using iOS 14 versions and above who do not have a choice to select a tracking option and cannot be tracked by default.
The Flurry blog (https://www.flurry.com/blog/) is an independent blog and has not been authorized, sponsored, or otherwise approved by Apple Inc.